As above, you have a really bad quality mic for recording (fine for playing, but you're going down a different route now). You can still get some high quality gaming headset mics, but there's lots of quality drop.
As for the banner, it's not bad but I'd say maybe add more than 2 game characters and also change the blue "Raw and uncut" colour as it doesn't stand out and really bleeds.
Your biggest problem, I would say, is that your banner shouts out "Marky" or "Marky Raw& Uncut" and completely overshadows that your actual channel handel is LongLiveMarky... you really should put that in your banner given that it's going to be the main thing that sticks in peoples minds.